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license: apache-2.0
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We have provided a presentation on the RRUFF data structure.

Diffraction data in the RRUFF database is recorded in two separate files:

- One, named "Powder_Xray_Data," stores diffraction data in reciprocal space.
- The other, named "Powder_DIF_File," stores crystal structures and the PDF (Pair Distribution Function) of the material.

We match these files by their code in the file names and search for the **X-RAY WAVELENGTH** to convert the reciprocal pattern to a real-space pattern that aligns with our data format in SimXRD.

Since the **X-RAY WAVELENGTH** is essential for acquiring XRD in real space, if the **X-RAY WAVELENGTH** is missing, we substitute it with a value of 1.54 Å (angstroms).

The potential reasons for the observed drop in classification accuracy are as follows:
+ File parsing may introduce minor errors.
+ Variations in diffraction ranges (diffraction angles 2θ/lattice plane distances) may not align perfectly with the settings in SimXRD, potentially introducing additional alignment challenges.
+ Some complex hydrated compounds in RRUFF have low purity and may not be suitable for testing.